P2257 — Secondary Air Injection System Control A Circuit Low
The control circuit of the secondary air injection system A reads a voltage below specification. Either the relay output is shorted to ground or the wiring/load is faulty.
General code reference. Confirm the definition and diagnostic procedure for your vehicle's year, model and engine. A stored code alone does not identify a failed part.
Affected components
- Secondary air pump
- Sai relay
- Sai wiring
Possible causes to check
These are possible checks, not a ranked diagnosis. Follow the vehicle manufacturer's test procedure before replacing parts.
- Control wire shorted to ground
- Faulty SAI relay
- Connector pins corroded - high contact resistance
Diagnostic notes
- The malfunction indicator lamp may illuminate
- This code can affect emissions
- A drive cycle may be required after repair
Related codes
Sources
Check each reference's vehicle and model-year scope. General background links do not establish which fault is most likely on your vehicle.
Diagnostic information is provided for reference only. Confirm the code with a compatible scan tool and follow the vehicle manufacturer's service procedures before replacing components.